WaterMarks Interview with Robert Twilley

Dr. Robert Twilley is a professor of biology and director of the Center for Ecology and Environmental Technology at the University of Louisiana in Lafayette. He is also lead author of "Confronting Climate Change in the Gulf Coast Region," a report of the Union of Concerned Scientists and the Ecological Society of America.

Dr. Robert Twilley

WATERMARKS: Let's begin with the basic question — is global climate change real?

TWILLEY: I can assure you, it's real. We have empirical evidence from highly credible sources showing that there's been an increase in the earth's air and water temperatures, a rise in sea level and shifts in patterns of precipitation. The debate in the scientific community isn't whether there is global climate change, but about the specific mechanisms that control change and what the magnitude of change will be in the future.

WATERMARKS: Isn't it possible that the climate change you're seeing is part of a natural cycle that will eventually reverse itself?

TWILLEY: Unfortunately, the human impact on our natural cycles is what is most disturbing. Let's use the example of CO2 concentrations. Core samples taken in Antarctica give us a definitive history of the level of CO2 in the atmosphere going back 170,000 years and covering four major climactic cycles. Up until recently, the very highest concentration of CO2 over that 170,000-year history was 280 parts per million. In 1954, however, concentrations were measured at 300 parts per million, an amount unprecedented until then. Today, the concentrations have jumped to 360 parts per million, an additional 20 percent increase over the previous high in less than 50 years. It's that kind of empirical evidence that has convinced the scientific community that what we're seeing is human adjustments of natural cycles.

A reminder that water levels change over time. Courtesy of NOAA Restoration Center, Erik Zobrist

WATERMARKS: Is it true that Louisiana is in greater danger from global climate change than other coastal states?

TWILLEY: Global climate change represents a greater risk for southern Louisiana than anyplace else in the nation. Because of the sedimentary composition of our deltaic plain, deeper regions of our marshes are sinking at the same time that the sea level is rising. So Louisiana can expect a combined, or relative, sea-level rise of at least 15 inches in the next 100 years — and up to 44 inches in some places. There's been a 2-inch relative sea-level rise in some regions over the last 10 years, which, given the flat slope of the coast, has put millions of dollars of taxpayer and corporate investments at risk because of the potential loss of infrastructure.

WATERMARKS: Does the private sector recognize the financial threat of sea-level rise in Louisiana?

TWILLEY: For the most part, the private sector can certainly appreciate the nature of the problem; it is a matter of whether they are willing to pay the costs inherent in the risks. But risk assessment is certainly familiar territory to the corporate world. British Petroleum just spent an additional $10 million in the construction of its new pipeline, partly because of the risk associated with sea-level rise. So the private sector knows what it means to protect an investment.

R. King Milling, president of Whitney National Bank and chair of the Louisiana Governor's Commission on Coastal Restoration and Conservation, has built tremendous awareness of the corporate risks to wetland loss and the need for immediate action. The equity that is lost each year with the disappearance of wetlands, and the risks to business investments has reached the highest levels of the private sector. Mr. Milling, and others like him, take this threat seriously.

WATERMARKS: What about a threat to CWPPRA's efforts to restore the coast? Is sea-level rise a factor?

TWILLEY: I think the most important word in the CWPPRA acronym is "planning." Every project, every design, every bit of engineering has to account for sea-level rise. It absolutely has to be one of the critical factors. If it's not, then I don't think there's been a buy-in to the idea of sustainability . . . to the idea that a project has a 20- or 30-year life span. Any project started today and intended to be producing results 10 years from now will be affected by sea-level rise.

The oil and gas industry is a big factor in the future of Louisiana's coastal wetlands. Courtesy of LA Department of Tourism

WATERMARKS: But aren't you talking about additional costs?

TWILLEY: When British Petroleum spent $10 million to account for future sea-level rise, it was adding value because the investment will significantly extend the life and therefore profitability of the new pipeline. CWPPRA projects will function in the same way. When you account for sea-level rise, then, and only then, can you calculate a cost-to-benefit ratio based on a 20- or 30-year life expectancy. The additional cost is really an investment in sustainability.

WATERMARKS: How do you respond when people say that the issue of global climate change is so complex that there's really nothing we can do to address it?

TWILLEY: I certainly agree that the issue is complex and oftentimes overwhelming. The bad news is that humans are part of the problem. The good news is the same — we are part of the problem. But it's only because we are connected to the problem that we have the capacity to deal with it. If global climate change were a force wholly outside of us, as suggested by the idea that it is only a 'natural cycle', then I'm afraid I'd see the situation as hopeless.

But because the human signature is all over global climate change, we aren't powerless. In fact, we've already demonstrated that we can correct serious problems in our global environment. For example, we recognized the symptoms of a depletion in our ozone levels, we diagnosed the problem, prescribed a cure, and guess what — the atmosphere responded.

I find it useful to compare our search for solutions to global climate change with our search for cures for the human body. We made great strides in medicine once we understood our own physiology. The same holds true for the earth. Once we understand the physiology of the earth, known as earth system science, we'll be much better at diagnosing its problems and finding the right planetary treatment to bring about a solution.

" ... like the human body, the earth has a great resiliency — far greater than many give it credit for. It's that remarkable resiliency that encourages me — it's where I find a great deal of hope." Courtesy of LA Department of Tourism

And like the human body, the earth has a great resiliency — far greater than many give it credit for. It's that remarkable resiliency that encourages me — it's where I find a great deal of hope. What we need now is the political and corporate will to become engaged in the problem.